Question 2
In the starch test, the leaf is boiled in alcohol in order to:
The right answer is the one marked above.
Dissolve the chlorophyll out of the leaf. Chlorophyll dissolves in alcohol; the alcohol turns green and the leaf turns white, so the iodine colour can then be seen.
Boiling in water is the step that kills the leaf and makes the membranes permeable. Two heatings, two different jobs — this is statement 2(ii) of the chapter exercise, and it is false as printed there because it names water.